Scheduling Design and Verification for Open Soft Real-time Systems

Open soft real-time systems, such as mobile robots, experience
unpredictable interactions with their environments and yet must
respond both adaptively and with reasonable temporal predictability.
New scheduling approaches are needed to address the demands of such
systems, in which many of the assumptions made by traditional
real-time scheduling theory do not hold. In previous work we
established foundations for a scheduling policy design and
verification approach for open soft real-time systems, the can use
different decision models, E.g., a Markov Decision Process (MDP), to
capture the nuances of their scheduling semantics.

However, several important refinements to the preliminary techniques
developed in that work are needed to make the approach applicable in
practice. This paper makes three main contributions to the state of
the art in scheduling open soft real-time systems: (1) it defines a
novel representation of the scheduling state space that is both more
compact and more expressive then the model defined in our previous
work,; (2) it exploits regular structure of that representation to
allow efficient verification of properties involving both discrete and
continuous system state variables, under specific scheduling policies;
and (3) it removes the unnecessary use of a time horizon in our
previous approach, thus allowing a more precise specification and
enforcement of a wider range of scheduling policies for open soft
real-time systems.

@techreport{wucse-2008-11, author = {Glaubius, Robert and Tidwell, Terry and Smart, William D. and Gill, Christopher D.}, title = {Scheduling Design and Verification for Open Soft Real-time Systems}, number = {{WUCSE-2008-11}}, institution = {Department of Computer Science and Engineering, Washington University in St. Louis}, month = {June}, year = {2008}}